testfiles/src/geom-pathstroke-test.cpp

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /**
   3  * @file Test the geom-pathstroke functionality.
   4  */
   5 /*
   6  * Authors:
   7  *   Hendrik Roehm <git@roehm.ws>
   8  *
   9  * Copyright (C) 2023 Authors
  10  *
  11  * Released under GNU GPL v2+, read the file 'COPYING' for more information.
  12  */
  13 #include "helper/geom-pathstroke.h"
  14
  15 #include <iostream>
  16 #include <gtest/gtest.h>
  17
  18 #include "object/sp-path.h"
  19 #include <2geom/pathvector.h>
  20 #include "svg/svg.h"
  21 #include "test-with-svg-object-pairs.h"
  22
  23 class GeomPathstrokeTest : public Inkscape::TestWithSvgObjectPairs
  24 {
  25 protected:
  26     GeomPathstrokeTest()
  27         : Inkscape::TestWithSvgObjectPairs("data/geom-pathstroke.svg", 8) {}
  28 };
  29
  30 double approximate_directed_hausdorff_distance(const Geom::Path *path1, const Geom::Path *path2)
  31 {
  32     auto const time_range = path1->timeRange();
  33     double dist_max = 0.;
  34     for (size_t i = 0; i <= 25; i += 1) {
  35         auto const time = time_range.valueAt(static_cast<double>(i) / 25);
  36         auto const search_point = path1->pointAt(time);
  37         Geom::Coord dist;
  38         path2->nearestTime(search_point, &dist);
  39         if (dist > dist_max) {
  40             dist_max = dist;
  41         }
  42     }
  43
  44     return dist_max;
  45 }
  46
  47 TEST_F(GeomPathstrokeTest, BoundedHausdorffDistance)
  48 {
  49     double const tolerance = 0.1;
  50     // same as 0.1 inch in the document (only works without viewBox and transformations)
  51     auto const offset_width = -9.6;
  52
  53     unsigned case_index = 0;
  54     for (auto test_case : getTestCases()) {
  55         auto const *test_item = cast<SPPath>(test_case.test_object);
  56         auto const *comp_item = cast<SPPath>(test_case.reference_object);
  57         ASSERT_TRUE(test_item && comp_item);
  58
  59         // Note that transforms etc are not considered. Therefore the objects shoud have equal transforms.
  60         auto const test_curve = test_item->curve();
  61         auto const comp_curve = comp_item->curve();
  62         ASSERT_TRUE(test_curve && comp_curve);
  63
  64         auto const &test_pathvector = test_curve->get_pathvector();
  65         auto const &comp_pathvector = comp_curve->get_pathvector();
  66         ASSERT_EQ(test_pathvector.size(), 1);
  67         ASSERT_EQ(comp_pathvector.size(), 1);
  68
  69         auto const &test_path = test_pathvector.at(0);
  70         auto const &comp_path = comp_pathvector.at(0);
  71
  72         auto const offset_path = Inkscape::half_outline(test_path, offset_width, 0, Inkscape::JOIN_EXTRAPOLATE, 0.);
  73         double const error1 = approximate_directed_hausdorff_distance(&offset_path, &comp_path);
  74         double const error2 = approximate_directed_hausdorff_distance(&comp_path, &offset_path);
  75         double const error = std::max(error1, error2);
  76
  77         EXPECT_LE(error, tolerance) << "Hausdorff distance above tolerance in test case #" << case_index
  78                                     << "\nactual d " << sp_svg_write_path(Geom::PathVector(offset_path), true)
  79                                     << "\nexpected d " << sp_svg_write_path(Geom::PathVector(comp_path), true)
  80                                     << std::endl;
  81         case_index++;
  82     }
  83 }
  84
  85 /*
  86   Local Variables:
  87   mode:c++
  88   c-file-style:"stroustrup"
  89   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
  90   indent-tabs-mode:nil
  91   fill-column:99
  92   End:
  93 */
  94 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :